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    <title>Document</title>
    <script>
        //封装一个数组去重的方法
        function unique(arr){
            var newArr = [];
            for(var i = 0;i < arr.length;i++){
                if(newArr.indexOf(arr[i])===-1){  //-1指的是该数组没有这个元素，就可以添加到新数组了
                    newArr.push(arr[i]);
                }
            }
            return newArr;
        }
        var demo = unique([1,3,2,1,5,6,4,5,6,7]);
        console.log(demo);

    </script>
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